Reporting and scheduling in an integrated access backhaul network

ABSTRACT

Wireless communications systems and methods related to communicating in an integrated access backhaul (IAB) network are provided. A first wireless communication device transmits to a second wireless device during a first one of a plurality of slots; and receives a second transmission from the second wireless device during a second one of the plurality of slots. The second transmission includes link quality information about the first transmission and scheduling information for a third transmission between the first and second wireless devices.

CLAIM OF PRIORITY UNDER 35 U.S.C. § 119

The present Applications for patent claims priority to ProvisionalApplication No. 62/722,332, entitled “REPORTING AND SCHEDULING IN ANINTEGRATED ACCESS BACKHAUL NETWORK” filed Aug. 24, 2018 and assigned tothe assignee hereof and hereby expressly incorporated by referenceherein

TECHNICAL FIELD

This application relates to wireless communication systems, and moreparticularly to communicating access data and backhaul data overwireless links in an integrated access backhaul (IAB) network.Embodiments enable and provide solutions and techniques forcommunication between wireless communication devices (e.g., basestations and user equipment devices (UEs)) in an IAB network.

INTRODUCTION

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include code division multiple access (CDMA)systems, time division multiple access (TDMA) systems, frequencydivision multiple access (FDMA) systems, and orthogonal frequencydivision multiple access (OFDMA) systems, (e.g., a Long Term Evolution(LTE) system). A wireless multiple-access communications system mayinclude several base stations (BSs), each simultaneously supportingcommunication for multiple communication devices, which may be otherwiseknown as user equipment (UE).

To meet the growing demands for expanded mobile broadband connectivity,wireless communication technologies are advancing from the LTEtechnology to a fifth generation (5G) new radio (NR) technology. 5G NRmay provide for access traffic and backhaul traffic at gigabit-levelthroughput. Access traffic refers to traffic between an access node(e.g., a base station) and a UE. Backhaul traffic refers to trafficbetween access nodes or traffic between an access node and a corenetwork.

BRIEF SUMMARY OF SOME EXAMPLES

The following summarizes some aspects of the present disclosure toprovide a basic understanding of the discussed technology. This summaryis not an extensive overview of all contemplated features of thedisclosure and is intended neither to identify key or critical elementsof all aspects of the disclosure nor to delineate the scope of any orall aspects of the disclosure. Its sole purpose is to present someconcepts of one or more aspects of the disclosure in summary form as aprelude to the more detailed description that is presented later.

For example, in an aspect of the disclosure, a method of wirelesscommunication may include transmitting, by the first wirelesscommunication device, a first transmission to the second wireless deviceduring a first one of the plurality of slots; and receiving, by thefirst wireless communication device, a second transmission from thesecond wireless device during a second one of the plurality of slots,the second transmission including link quality information about thefirst transmission and scheduling a third transmission between the firstand second wireless devices.

In some aspects, a method of wireless communication may includetransmitting, by the first wireless communication device, a firsttransmission to the second wireless device during a first one of theplurality of slots; and receiving, by the first wireless communicationdevice, a second transmission from the second wireless device during asecond one of the plurality of slots, the second transmission includinglink quality information about the first transmission and scheduling athird transmission between the first and second wireless devices,wherein the third transmission is transmitted by the second node andreceived by the first node.

In another aspect, a method of wireless communication may includetransmitting, by the first wireless communication device, a firsttransmission to the second wireless device during a first one of theplurality of slots; and receiving, by the first wireless communicationdevice, a second transmission from the second wireless device during asecond one of the plurality of slots, the second transmission includinglink quality information about the first transmission and scheduling athird transmission between the first and second wireless devices,wherein the third transmission is transmitted by the first node andreceived by the second node.

In the foregoing aspects, each of the plurality of slots may include acontrol channel and a data channel, and the link quality information istransmitted in a control channel of the second slot or in a data channelof the second slot. In another aspect each of the plurality of slotsincludes a control channel and a data channel, and the ACK/NACK istransmitted in a control channel of the second slot or in a data channelof the second slot.

In some aspects a method of wireless communication may includetransmitting, by the first wireless communication device, a firsttransmission to the second wireless device during a first one of theplurality of slots; and receiving, by the first wireless communicationdevice, a second transmission from the second wireless device during asecond one of the plurality of slots, the second transmission includinglink quality information about the first transmission and scheduling athird transmission between the first and second wireless devices,wherein the link quality information about the first transmissionincludes a least one or more combinations of CQI, reference signalreceived power (RSRP), signal to noise ratio (SNR), reference signalreceived quality (RSRQ), RSSI, beam index, beam coherence time, and beamquality.

In some aspects a method of wireless communication may includetransmitting, by the first wireless communication device, a firsttransmission to the second wireless device during a first one of theplurality of slots; and receiving, by the first wireless communicationdevice, a second transmission from the second wireless device during asecond one of the plurality of slots, the second transmission includinglink quality information about the first transmission and scheduling athird transmission between the first and second wireless devices,wherein the second transmission includes an ACK/NACK for datatransmitted during the first transmission.

In other aspects, a method of wireless communication may includetransmitting, by the first wireless communication device, a firsttransmission to the second wireless device during a first one of theplurality of slots; and receiving, by the first wireless communicationdevice, a second transmission from the second wireless device during asecond one of the plurality of slots, the second transmission includinglink quality information about the first transmission and scheduling athird transmission between the first and second wireless devices,wherein the second transmission includes a scheduling request (SR) forthe first device to send a fourth transmission to the second device. TheSR may be transmitted in a control channel or in a data channel.

In other aspects, user equipment for wireless communications may includea radio transceiver; a processor; and a memory; wherein the processor isin electrical communication with the transceiver and the memory; andwherein the memory is configured with instructions to cause theprocessor to implement any of the methods of the preceding aspects.

Other aspects, features, and embodiments of the present invention willbecome apparent to those of ordinary skill in the art, upon reviewingthe following description of specific, exemplary embodiments of thepresent invention in conjunction with the accompanying figures. Whilefeatures of the present invention may be discussed relative to certainembodiments and figures below, all embodiments of the present inventioncan include one or more of the advantageous features discussed herein.In other words, while one or more embodiments may be discussed as havingcertain advantageous features, one or more of such features may also beused in accordance with the various embodiments of the inventiondiscussed herein. In similar fashion, while exemplary embodiments may bediscussed below as device, system, or method embodiments it should beunderstood that such exemplary embodiments can be implemented in variousdevices, systems, and methods.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a wireless communication network according toembodiments of the present disclosure.

FIG. 2 illustrates an integrated access backhaul (IAB) network accordingto embodiments of the present disclosure.

FIG. 3 illustrates an IAB network topology according to embodiments ofthe present disclosure.

FIGS. 4A and 4B illustrate sidelink communications according toembodiments of the present disclosure.

FIGS. 5A, 5B, and 5C illustrate various slot formats that may be usedfor communications between the nodes of FIGS. 1 and 2.

FIG. 6 illustrates an IAB network resource sharing method according toembodiments of the present disclosure.

FIGS. 7A to 7D illustrate various aspects of communicating data andcontrol information in sidelink formatted slots according to embodimentsof the present disclosure.

FIG. 8 is a block diagram of an exemplary user equipment (UE) accordingto embodiments of the present disclosure.

FIG. 9 is a block diagram of an exemplary base station (BS) according toembodiments of the present disclosure.

FIG. 10 illustrates a method of communication using sidelinks accordingto embodiments of the present disclosure.

DETAILED DESCRIPTION

The detailed description set forth below, in connection with theappended drawings, is intended as a description of variousconfigurations and is not intended to represent the only configurationsin which the concepts described herein may be practiced. The detaileddescription includes specific details for the purpose of providing athorough understanding of the various concepts. However, it will beapparent to those skilled in the art that these concepts may bepracticed without these specific details. In some instances, well-knownstructures and components are shown in block diagram form to avoidobscuring such concepts.

Techniques described herein may be used for various wirelesscommunication networks such as code-division multiple access (CDMA),time-division multiple access (TDMA), frequency-division multiple access(FDMA), orthogonal frequency-division multiple access (OFDMA),single-carrier FDMA (SC-FDMA) and other networks. The terms “network”and “system” are often used interchangeably. A CDMA network mayimplement a radio technology such as Universal Terrestrial Radio Access(UTRA), cdma2000, etc. UTRA includes Wideband CDMA (WCDMA) and othervariants of CDMA. cdma2000 covers IS-2000, IS-95 and IS-856 standards. ATDMA network may implement a radio technology such as Global System forMobile Communications (GSM). An OFDMA network may implement a radiotechnology such as Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB),IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDMA, etc.UTRA and E-UTRA are part of Universal Mobile Telecommunication System(UMTS). 3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A) are newreleases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A and GSMare described in documents from an organization named “3rd GenerationPartnership Project” (3GPP). CDMA2000 and UMB are described in documentsfrom an organization named “3rd Generation Partnership Project 2”(3GPP2). The techniques described herein may be used for the wirelessnetworks and radio technologies mentioned above as well as otherwireless networks and radio technologies, such as a next generation(e.g., 5^(th) Generation (5G) operating in mmWave bands) network.

The present disclosure describes mechanisms for communicating in an IABnetwork. An IAB network may include a combination of wireless accesslinks between BSs and UEs and wireless backhaul links between the BSs.The IAB network may employ a multi-hop topology (e.g., a spanning tree)for transporting access traffic and backhaul traffic. One of the BSs maybe configured with an optical fiber connection in communication with acore network, where the BS may function as an anchoring node (e.g., aroot node) to transport backhaul traffic between the core network andthe IAB network. The other BSs may be referred to as relay nodes in thenetwork. Each BS may have one or more parent nodes, which may includeother BSs, and/or one or more child nodes, which may include other BSsand/or UEs. The UEs may function as child nodes. In some embodiments,UEs may also function as relay nodes. The parent nodes may function asaccess nodes to the child nodes and may be referred to as accessfunctionality (ACF)-nodes. The child nodes may function as UEs to theparent nodes and may be referred to as UE functionality (UEF)-nodes.Thus, a BS may function as an ACF-node when communicating with a childnode and may function as a UEF-node when communicating with a parentnode. The disclosed embodiments provide efficient mechanisms forcommunication between nodes in an IAB network. A pair of nodes for whichone node is in the path of communication between the other node and thecore network may be referred to as having a parent-child relationship.

In an embodiment, a method of wireless communication may includetransmitting, by the first wireless communication device, a firsttransmission to the second wireless device during a first one of theplurality of slots; and receiving, by the first wireless communicationdevice, a second transmission from the second wireless device during asecond one of the plurality of slots, the second transmission includinglink quality information about the first transmission and scheduling athird transmission between the first and second wireless devices.

In another embodiment, a method of wireless communication may includetransmitting, by the first wireless communication device, a firsttransmission to the second wireless device during a first one of theplurality of slots; and receiving, by the first wireless communicationdevice, a second transmission from the second wireless device during asecond one of the plurality of slots, the second transmission includinglink quality information about the first transmission and scheduling athird transmission between the first and second wireless devices,wherein the third transmission is transmitted by the second node andreceived by the first node.

In another embodiment, a method of wireless communication may includetransmitting, by the first wireless communication device, a firsttransmission to the second wireless device during a a first one of theplurality of slots; and receiving, by the first wireless communicationdevice, a second transmission from the second wireless device during asecond one of the plurality of slots, the second transmission includinglink quality information about the first transmission and scheduling athird transmission between the first and second wireless devices,wherein the third transmission is transmitted by the first node andreceived by the second node.

In the foregoing embodiment, each of the plurality of slots may includea control channel and a data channel, and the link quality informationis transmitted in a control channel of the second slot or in a datachannel of the second slot. In another aspect each of the plurality ofslots includes a control channel and a data channel, and the ACK/NACK istransmitted in a control channel of the second slot or in a data channelof the second slot.

In some embodiments, a method of wireless communication may includetransmitting, by the first wireless communication device, a firsttransmission to the second wireless device during a first one of theplurality of slots; and receiving, by the first wireless communicationdevice, a second transmission from the second wireless device during asecond one of the plurality of slots, the second transmission includinglink quality information about the first transmission and scheduling athird transmission between the first and second wireless devices,wherein the link quality information about the first transmissionincludes a least one or more combinations of CQI, reference signalreceived power (RSRP), signal to noise ratio (SNR), reference signalreceived quality (RSRQ), RSSI, beam index, beam coherence time, and beamquality.

In an embodiment, a method of wireless communication may includetransmitting, by the first wireless communication device, a firsttransmission to the second wireless device during a first one of theplurality of slots; and receiving, by the first wireless communicationdevice, a second transmission from the second wireless device during asecond one of the plurality of slots, the second transmission includinglink quality information about the first transmission and scheduling athird transmission between the first and second wireless devices,wherein the second transmission includes an ACK/NACK for datatransmitted during the first transmission.

In another embodiment, a method of wireless communication may includetransmitting, by the first wireless communication device, a firsttransmission to the second wireless device during a first one of theplurality of slots; and receiving, by the first wireless communicationdevice, a second transmission from the second wireless device during asecond one of the plurality of slots, the second transmission includinglink quality information about the first transmission and scheduling athird transmission between the first and second wireless devices,wherein the second transmission includes a scheduling request (SR) forthe first device to send a fourth transmission to the second device. TheSR may be transmitted in a control channel or in a data channel.

In some embodiments, user equipment for wireless communications mayinclude a radio transceiver; a processor; and a memory; wherein theprocessor is in electrical communication with the transceiver and thememory; and wherein the memory is configured with instructions to causethe processor to implement any of the methods of the preceding aspects.

The forgoing aspects of the present application can provide severalbenefits. For example, routing data through sidelinks may reduce thenumber of hops needed to get data to its destination, thereby reducinglatency and improving reliability. Using sidelink may also improveoverall network capacity by reducing the amount of traffic in uplink ordownlink transmissions.

FIG. 1 illustrates a wireless communication network 100 including aplurality of BSs 105, a plurality of UEs 115, and a core network 130.The network 100 may be an LTE network, an LTE-A network, a millimeterwave (mmW) network, a new radio (NR) network, a 5G network, or any othersuccessor network to LTE.

The BSs 105 may wirelessly communicate with the UEs 115 via one or moreBS antennas. Each BS 105 may provide communication coverage for arespective geographic coverage area 110. In 3GPP, the term “cell” canrefer to this geographic coverage area of a BS and/or a BS subsystemserving the coverage area, depending on the context in which the term isused. In the example shown in FIG. 1, the BSs 105 a, 105 b, 105 c, 105d, and 105 e are examples of macro BSs for the coverage areas 110 a, 110b, 110 c, 110 d, and 110 e, respectively.

Communication links 125 shown in the network 100 may include uplink (UL)transmissions from a UE 115 to a BS 105, or downlink (DL) transmissions,from a BS 105 to a UE 115. The communication links 125 are referred toas wireless access links. The UEs 115 may be dispersed throughout thenetwork 100, and each UE 115 may be stationary or mobile. A UE 115 mayalso be referred to as a mobile station, a subscriber station, a mobileunit, a subscriber unit, a wireless unit, a remote unit, a mobiledevice, a wireless device, a wireless communications device, a remotedevice, a mobile subscriber station, an access terminal, a mobileterminal, a wireless terminal, a remote terminal, a handset, a useragent, a mobile client, a client, or some other suitable terminology. AUE 115 may also be a cellular phone, a personal digital assistant (PDA),a wireless modem, a wireless communication device, a handheld device, atablet computer, a laptop computer, a cordless phone, a personalelectronic device, a handheld device, a personal computer, a wirelesslocal loop (WLL) station, an Internet of things (IoT) device, anInternet of Everything (IoE) device, a machine type communication (MTC)device, an appliance, an automobile, or the like.

The BSs 105 may communicate with the core network 130 and with oneanother via optical fiber links 134. The core network 130 may provideuser authentication, access authorization, tracking, Internet Protocol(IP) connectivity, and other access, routing, or mobility functions. Atleast some of the BSs 105 (e.g., which may be an example of an evolvedNodeB (eNB), a next generation NodeB (gNB), or an access node controller(ANC)) may interface with the core network 130 through the backhaullinks 134 (e.g., S1, S2, etc.) and may perform radio configuration andscheduling for communication with the UEs 115. In various examples, theBSs 105 may communicate, either directly or indirectly (e.g., throughcore network 130), with each other over the backhaul links 134 (e.g.,X1, X2, etc.).

Each BS 105 may also communicate with other UEs 115 through a number ofother BSs 105, where the BS 105 may be an example of a smart radio head.In alternative configurations, various functions of each BS 105 may bedistributed across various BSs 105 (e.g., radio heads and access networkcontrollers) or consolidated into a single BS 105.

FIG. 2 illustrates an IAB network 200 according to embodiments of thepresent disclosure. The network 200 is substantially similar to thenetwork 100 in many respects. For example, the BSs 105 communicates withthe UEs 115 over the wireless access links 125. However, in the network200, only some BSs (e.g., the BS 105 c) are connected to the corenetwork by high capacity link, such as optical fiber backhaul link 134.Other BSs 105 a, 105 b, 105 d, and 105 e wirelessly communicate witheach other and with the BS 105 c over wireless backhaul links 234. TheBS 105 c connected to the optical fiber backhaul link 134 may functionas an anchor for the other BSs 105 a, 105 b, 105 d, and 105 e tocommunicate the core network 130, as described in greater detail herein.The wireless access links 125 and the wireless backhaul links 234 mayshare resources for communications in the network 200. The network 200may also be referred to as a self-backhauling network. The network 200can improve wireless link capacity, reduce latency, and reducedeployment cost.

In an embodiment, network 200 may use millimeter wave (mmWav) frequencybands for communications. In such a network, some of BSs 105 a, 105 b,105 d, and 105 e may communicate with each other and with BS 105 c usingnarrow directional beams for wireless links 234. The BSs 105 may alsocommunicate with the UEs 115 using narrow directional beams for wirelesslinks 125. The directional beams for links 234 may be substantially likethe directional beams for links 125. For example, the BSs 105 may useanalog beamforming and/or digital beamforming to form the directionalbeams for transmission and/or reception. Similarly, UEs 115 may useanalog beamforming and/or digital beamforming to form the directionalbeams for transmission and/or reception. Using narrow directional beamsmay minimize or reduce inter-link interference, thereby increasingnetwork throughput and reducing latency. Thus, the use of mmWav canimprove system performance.

In some implementations, the networks 100 and 200 may use orthogonalfrequency division multiplexing (OFDM) on the downlink andsingle-carrier frequency division multiplexing (SC-FDM) on the UL. OFDMand SC-FDM partition the system bandwidth into multiple (K) orthogonalsubcarriers, which are also commonly referred to as tones, bins, or thelike. Each subcarrier may be modulated with data. In general, modulationsymbols are sent in the frequency domain with OFDM and in the timedomain with SC-FDM. The spacing between adjacent subcarriers may befixed, and the total number of subcarriers (K) may be dependent on thesystem bandwidth. The system bandwidth may also be partitioned intosubbands.

In an embodiment, the BSs 105 can assign or schedule transmissionresources (e.g., in the form of time-frequency resource blocks) for DLand UL transmissions in the network 100. DL refers to the transmissiondirection from a BS 105 to a UE 115, whereas UL refers to thetransmission direction from a UE 115 to a BS 105. The communication canbe in the form of radio frames. A radio frame may be divided into aplurality of subframes, for example, about 10. Each subframe can bedivided into slots, for example, about 2. In a frequency-divisionduplexing (FDD) mode, simultaneous UL and DL transmissions may occur indifferent frequency bands. For example, each subframe includes a ULsubframe in a UL frequency band and a DL subframe in a DL frequencyband. In a time-division duplexing (TDD) mode, UL and DL transmissionsoccur at different time periods using the same frequency band. Forexample, a subset of the subframes (e.g., DL subframes) in a radio framemay be used for DL transmissions and another subset of the subframes(e.g., UL subframes) in the radio frame may be used for ULtransmissions.

The DL subframes and the UL subframes can be further divided intoseveral regions. For example, each DL or UL subframe may havepre-defined regions for transmissions of reference signals, controlinformation, and data. Reference signals are predetermined signals thatfacilitate the communications between the BSs 105 and the UEs 115. Forexample, a reference signal can have a predefined pilot pattern orstructure, where pilot tones may span across an operational bandwidth orfrequency band, each positioned at a pre-defined time and a pre-definedfrequency. For example, a BS 105 may transmit cell-specific referencesignals (CRSs) and/or channel state information-reference signals(CSI-RSs) to enable a UE 115 to estimate a DL channel. Similarly, a UE115 may transmit sounding reference signals (SRSs) to enable a BS 105 toestimate a UL channel. Control information may include resourceassignments and protocol controls. Data may include protocol data and/oroperational data. In some embodiments, the BSs 105 and the UEs 115 maycommunicate using self-contained subframes. A self-contained subframemay include a portion for DL communication and a portion for ULcommunication. A self-contained subframe can be DL-centric orUL-centric. A DL-centric subframe may include a longer duration for DLcommunication than UL communication. A UL-centric subframe may include alonger duration for UL communication than UL communication.

FIG. 3 illustrates a network topology 300 according to embodiments ofthe present disclosure. The topology 300 can be employed by the network200. For example, the BSs 105 and the UEs 115 can be configured to forma logical spanning tree configuration as shown in the topology 300 forcommunicating access traffic and/or backhaul traffic. The topology 300may include an anchor 310 coupled to an optical fiber link 134 forcommunication with a core network (e.g., the core network 130). Theanchor 310 may correspond to the BS 105 c in the network 200.

The topology 300 includes a plurality of logical levels 302. In theexample of FIG. 3, the topology 300 includes three levels 302, shown as302 a, 302 b, and 302 c. In some other embodiments, the topology 300 caninclude any suitable number of levels 302 (e.g., two, three, four, five,or six, etc.). Each level 302 may include a combination of UEs 115 andBSs 105 interconnected by logical links 304, shown as 304 a, 304 b, and304 c. For example, a logical link 304 between a BS 105 and a UE 115 maycorrespond to a wireless access link 125, whereas a logical link 304between two BSs 105 may correspond to a wireless backhaul link 234. TheBSs 105 and the UEs 115 may be referred to as relay nodes in thetopology 300.

The nodes (e.g., the BSs 105) in the level 302 a can function as relaysfor the nodes in the level 302 b, for example, to relay backhaul trafficbetween the nodes and the anchor 310. Similarly, the nodes (e.g., theBSs 105) in the level 302 b can function as relays for the nodes in thelevel 302 c. For example, the nodes in the level 302 a are parent nodesto the nodes in the level 302 b, and the nodes in the level 302 c arechild nodes to the nodes in level 302 b. The parent nodes may functionas ACF-nodes and the child nodes may function as UEF-nodes.

For example, a BS 105 may implement both ACF and UEF and may function asan ACF-node and an UEF-node depending on which node the BS iscommunicating with. For example, a BS 105 (shown as pattern-filled) inthe level 302 b may function as an access node when communicating with aBS 105 or a UE 115 in the level 302 c. Alternatively, the BS 105 mayfunction as a UE when communicating with a BS 105 in the level 302 a.When a communication is with a node in a higher level or with a smallernumber of hops to the anchor 310, the communication is referred to as aUL communication. When a communication is with a node in a lower levelor with a greater number of hops to the anchor 310, the communication isreferred to as a DL communication. In some embodiments, the anchor 310may allocate resources for the links 304. Mechanisms for scheduling ULand DL transmissions and/or allocating resources based on the topology300 are described in greater detail herein.

In addition to logical links 304, network topology 300 may also includeadditional links 306 between BSs 105. Links 306 may link BSs that do nothave a parent-child relationship in network topology 300 and may linkarbitrary BSs in the same or different layers of the topology.Advantageously, links 306, referred to as sidelinks herein, may providean alternate path for routing communications between BSs 105 and UEs115. For example, with sidelink 306, communications between UE 115 a andUE 115 b may be routed from BS 105 a to BS 105 b via sidelink 306,rather than up through layers 302 b and 302 a to anchor 310 then backdown to UE 155 b.

FIGS. 4A and 4B show possible resource partitioning in accordance withaspects disclosed herein. In an aspect, networks may be constrainedinterference between nearby BSs and other considerations, such ashalf-duplex constraints. For example, UL/DL transmissions between BS 310and BSs 105 may be scheduled during a first slot, or time period, whileUL/DL transmissions between BSs 105 and UEs 115, may be scheduled duringa different slot. Typically, such slots alternate between transmittingand receiving. In an aspect, a third slot may be used for side linkcommunication. This is shown in FIG. 4A, wherein available resources arepartitioned between DL, UL and sidelink communications as shown by theline style if the link. The resources may be rotated between thedifferent types of communications in a round robin, or other schedulingscheme.

In another aspect, a BSs 105 may be able to use beam forming techniquesto communicate with neighboring BSs. The use of narrow beams reducesinterference to other wireless devices in the network. In such anetwork, BSs 105 may communicate without requiring resource allocationfrom the typical UL/DL slots. This is shown in FIG. 4B, wherein BSs 105a and 105 b transmit to each other in alternate slots. That is, BS 105 atransmits to BS 105 b in a first set of slots, 1→2, and BS 105 btransmits to BS 105 a during a second set of slots, 2→1. In an aspect,the slots need not alternate in a fixed 1:1 ratio, but may vary based onload, QoS, and other factors.

FIGS. 5A, 5B, and 5C illustrate various slot formats that may be usedfor communications between the nodes of FIGS. 1 and 2. FIG. 5A showsexemplary downlink (DL) centric slot 500 which may be used fortransmitting from a higher level node to a lower level node, e.g. BS 105to UE 115 a in FIG. 1 or 2. DL centric slot 500 includes PDCCH 502,PDSCH 504, gap 506 and PUCCH 508. PDCCH 502 is used to send controlinformation such as DL/UL resource assignments, power control commands,paging indicators, and the like, whereas PDSCH 504 carries applicationdata. Gap 506 provides time for the receiving device, e.g., UE 115, toprocess PDCCH 502 and PDSCH 504 and to reconfigure for transmitting.PUCCH 502 may be used for the receiver to send uplink controlinformation, such as ACK/NACK and power control signaling back to thesender.

FIG. 5B illustrates uplink (UL) centric slot 510 which may be used fortransmissions from a lower order node to a higher order node. UL centricslot 510 may include PDCCH 512, gap 516, and PUSCH 518. PUSCH may beused to send data, such as application data. Gap 516 provides time forthe receiving device, e.g., UE 115, to process PDCCH 512 to determinewhich resources it is allocated in PUSCH 518 and to turn it transceiverfrom a receiving mode to a transmitting mode.

FIG. 5C illustrates sidelink (SL) centric slot 520 which may be used fortransmissions between nodes that are at the same order or level in thenetwork topology. Sidelink slot 520, may be used for communicationsbetween nodes that are not otherwise directly linked by the logicaltopology of a network. Sidelink slot 520 includes PDCCH 522 and PDSCH524, which serve similar roles to the corresponding slots of downlinkcentric slot 500 of FIGS. 5A and 5B. SL centric slot 520 may includePDCCH 522, PDSCH 528, gap 526. PDSCH may be used to send data, such asapplication and other data between BSs 105. Gap 526 provides time forthe receiving device, e.g., UE 115, to process data in PDSCH 526 and toturn it transceiver from a receiving mode to a transmitting mode inanticipation or transmitting data in the reverse direction.

FIG. 6 illustrates an IAB network resource sharing method 600 accordingto embodiments of the present disclosure. The method 600 illustratesresource partitioning for use in the topology 300. In FIG. 6, the x-axisrepresents time in some constant units (e.g., frames, slots, subslots,msec, symbols, etc.). The method 600 time-partitions resources in an IABnetwork (e.g., the network 200) into resources 610 and 620. Theresources 610 and 620 can include time-frequency resources. For example,each resource 610 or 620 may include a number of symbols (e.g., OFDMsymbols) in time and a number of subcarriers in frequency. In someembodiments, each resource 610 or 620 shown may correspond to asubframe, a slot, or a transmission time interval (TTI), which may carryone media access control (MAC) layer transport block.

As will be discussed below, sidelink resources may alternate directionfor transmissions: first from BS 105 a to BS 105 b and then the reverse.Accordingly, rather than providing PUCCH and PUSCH for sidelink slots,the information normally carried in these channels may be carried in thePDCCH or PDSCH when the direction of transmission is reversed.

As an example, the method 600 may assign the resources 610 to the links304 a and 304 c in the topology 300 for communicating UL and/or DLtraffic. The method 600 may assign the resources 620 to the links 304 bin the topology 300 for communicating UL and/or DL traffic. Thetime-partitioning of the resources in the alternating manner shown inthe method 600 can reduce interference between the different levels 302,reducing constraints due to half-duplexing, and reduce transmit-receivegap periods.

FIGS. 7A to 7C illustrate various aspects of communicating data andcontrol information in sidelink formatted slots. In a first aspect,shown in FIG. 7A, BS 105 a transmits PDCCH 702 a including schedulinginformation about which resources in PDSCH 704 a contain data beingtransmitted to BS 105 b. BS 105 a subsequently transmits the data inPDSCH 704 a in accordance with the scheduling information transmittedduring PDCCH 702 a. BS 105 b, having received the scheduling informationin PDCCH 702 a, decodes PDSCH 704 a to receive the data communicatedfrom BS 105 a. After gap 706, BS 105 b transmits scheduling informationand data during PSCCH 702 b and PDSCH 704 b. In addition, BS 105 b mayalso transmit control information during PDCCH 702 b, such as linkquality information and ACK/NACK information. In another aspect, BS 105b may transmit the control information during PDSCH 714 b rather thanduring PDCCH 712 b, as shown in FIG. 7C.

In an aspect, additional signals and control information may be neededin a narrow beam mmWave environment. For example, BSs 105 a and 105 bmay need to be able to determine which beam(s) to use for communication.In an aspect, BS 105 a may transmit CSI-RS during PDSCH 724 a by sendingCSI-RS signaling over multiple beams in a sweeping manner. BS 105 b maycommunication a desired beam index during subsequent PDCCH 722 b, asshown in FIG. 7C. In an aspect, BS 105 b may alternately communicatebeam selection information during PDSCH 724 b. The preceding describedtransmissions from BS 105 a to BS 105 b, whereas one skilled in the artwill understand that transmissions in the reverse direction, e.g., fromBS 105 b to BS 105 a, are made in an analogous manner.

In an aspect of the invention, sidelink resources 830 may beinterspersed with uplink resources 810 and downlink resources 820, asshown in FIG. 8, so that gap 726 does not explicitly need to be includedin the sidelink slot format. In another aspect, narrow beam mmWavetransmissions may obviate the need to time multiplex resources 810, 820,and 830.

Regular PUCCH channels include information needed for downlinktransmissions, such as ACK/NAK of downlink traffic, channel qualityinformation (e.g., CQI, RSRP, PMI), scheduling requests, beam indexreports, and beam quality reports, among others. Because the sidelinkslot format does not include a PUCCH, this information is conveyedthrough other mechanisms. In one aspect, the PUCCH-type information isconveyed in the PDCCH when a sidelink transmission is sent in thereverse direction. For example, when BS 105 b received a transmissionfrom BS 105 a, the information usually sent during PUCCH is transmittedin the PDCCH when BS 105 b transmits to BS 105 a. Advantageously,control channels are typically more robust than data channels. Inanother aspect, the PUCCH-type information may be conveyed in the PDSCHwhen a sidelink transmission is sent in the reverse direction. Forexample, when BS 105 b receives a transmission from BS 105 a, theinformation usually sent during PUCCH may transmitted in PDSCH when BS105 b transmits to BS 105 a.

FIG. 7D illustrates resource sharing in an IAB network, such as thetopology 300, according to embodiments of the present disclosure. InFIG. 7D, the x-axis represents time in some constant units (e.g.,frames, slots, subslots, msec, etc.). As shown, resources in an IABnetwork (e.g., the network 200) are time-partitioned into resources 760,770, and 780. The resources may include time-frequency resources. Forexample, each resource 760, 770, and 780 may include a number of symbols(e.g., OFDM symbols) in time and a number of subcarriers in frequency.In some embodiments, each resource 760, 770, and 780 shown maycorrespond to a subframe, a slot, a transmission time interval (TTI), orother convenient interval, which may carry one media access control(MAC) layer transport block.

As an example, in topology 300 of FIG. 3, resources 760 may be assignedto links 304 a and 304 c for communicating UL and/or DL traffic; theresources 770 may be assigned to the links 304 b for communicating ULand/or DL traffic; and the resources 780 may be assigned to 306 forcommunicating sidelink traffic. The time-partitioning of the resourcesin the alternating manner shown in FIG. 7D can reduce interferencebetween the different levels 302, overcome the half-duplex constraint,and reduce transmit-receive gap periods.

In an aspect of the present invention, resource partitioning to providesidelink 306 is done at a node or anchor having a higher order than thenodes sharing sidelink 306, that is, one at a higher level in networktopology 300. In an aspect, the resource partitioning is done at acommon parent of the two nodes using the sidelink. For instance, anchor310 may partition network resources into resources 310, 320, and 330 forall the nodes in FIG. 3. Partitioning may also be done by non-anchornodes that are higher than the nodes using the sidelink.

In an aspect of setting up sidelink 306, the direction of communicationbetween BSs 105 a and 105 b will typically alternate. That is a resourcepartition may be used for transmission of data from BS 105 a to BS 105b, then a subsequent resource partition may be used for transmissionsfrom BS105 b to BS105 a. In some embodiments, the resource partitionsmay be substantially the same size in terms of time, bandwidth, and thelike. In other embodiments, the resource partitions may have differentsizes to accommodate different data rates, bandwidth, channelconditions, reliability, quality of service, etc. For example,transmitting video from UE 115 a to UE 115 b may require largerpartitions or more partitions for transmission of data from BS 105 a toBS 105 b than are needed to transmit control information in the reversedirection from BS 105 b to BS 105 a.

FIG. 8 is a block diagram of an exemplary UE 800 according toembodiments of the present disclosure. The UE 800 may be a UE 115 asdiscussed above. As shown, the UE 800 may include a processor 802, amemory 804, an IAB communication module 808, a transceiver 810 includinga modem subsystem 812 and a radio frequency (RF) unit 814, and one ormore antennas 816. These elements may be in direct or indirectcommunication with each other, for example via one or more buses.

The processor 802 may include a central processing unit (CPU), a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), a controller, a field programmable gate array (FPGA) device,another hardware device, a firmware device, or any combination thereofconfigured to perform the operations described herein. The processor 802may also be implemented as a combination of computing devices, e.g., acombination of a DSP and a microprocessor, a plurality ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration.

The memory 804 may include a cache memory (e.g., a cache memory of theprocessor 802), random access memory (RAM), magnetoresistive RAM (MRAM),read-only memory (ROM), programmable read-only memory (PROM), erasableprogrammable read only memory (EPROM), electrically erasableprogrammable read only memory (EEPROM), flash memory, solid state memorydevice, hard disk drives, other forms of volatile and non-volatilememory, or a combination of different types of memory. In an embodiment,the memory 804 includes a non-transitory computer-readable medium. Thememory 804 may store instructions 806. The instructions 806 may includeinstructions that, when executed by the processor 802, cause theprocessor 802 to perform the operations described herein with referenceto the UEs 115 in connection with embodiments of the present disclosure.Instructions 806 may also be referred to as code. The terms“instructions” and “code” should be interpreted broadly to include anytype of computer-readable statement(s). For example, the terms“instructions” and “code” may refer to one or more programs, routines,sub-routines, functions, procedures, etc. “Instructions” and “code” mayinclude a single computer-readable statement or many computer-readablestatements.

The IAB communication module 808 may be implemented via hardware,software, or combinations thereof. For example, the IAB communicationmodule 808 may be implemented as a processor, circuit, and/orinstructions 806 stored in the memory 804 and executed by the processor802. The IAB communication module 808 may be used for various aspects ofthe present disclosure. For example, the IAB communication module 808 isconfigured to maintain multiple synchronization references, providesynchronization information (e.g., including timing and/or frequency)associated with the synchronization references to other nodes (e.g., theBSs 105), receive synchronization information from other nodes, receivesynchronization adjustment commands, receive scheduling information(e.g., gap periods, transmission timing, and/or reception timing),adjust synchronization references based on the received synchronizationinformation and/or the received commands, and/or communicate with othernodes based on received scheduling information, as described in greaterdetail herein.

As shown, the transceiver 810 may include the modem subsystem 812 andthe RF unit 814. The transceiver 810 can be configured to communicatebi-directionally with other devices, such as the BSs 105. The modemsubsystem 812 may be configured to modulate and/or encode the data fromthe memory 804 and/or the IAB communication module 808 according to amodulation and coding method (MCS), e.g., a low-density parity check(LDPC) coding method, a turbo coding method, a convolutional codingmethod, a digital beamforming method, etc. The RF unit 814 may beconfigured to process (e.g., perform analog to digital conversion ordigital to analog conversion, etc.) modulated/encoded data from themodem subsystem 812 (on outbound transmissions) or of transmissionsoriginating from another source such as a UE 115 or a BS 105. The RFunit 814 may be further configured to perform analog beamforming inconjunction with the digital beamforming. Although shown as integratedtogether in transceiver 810, the modem subsystem 812 and the RF unit 814may be separate devices that are coupled together at the UE 115 toenable the UE 115 to communicate with other devices.

The RF unit 814 may provide the modulated and/or processed data, e.g.data packets (or, more generally, data messages that may contain one ormore data packets and other information), to the antennas 816 fortransmission to one or more other devices. This may include, forexample, transmission of reservation signals, reservation responsesignals, and/or any communication signal according to embodiments of thepresent disclosure. The antennas 816 may further receive data messagestransmitted from other devices. This may include, for example, receptionof synchronization information, synchronization adjustment commands,and/or scheduling adjustment information according to embodiments of thepresent disclosure. The antennas 816 may provide the received datamessages for processing and/or demodulation at the transceiver 810. Theantennas 816 may include multiple antennas of similar or differentdesigns in order to sustain multiple transmission links. The RF unit 814may configure the antennas 816.

FIG. 9 is a block diagram of an exemplary BS 900 according toembodiments of the present disclosure. The BS 900 may be a BS 105 asdiscussed above. A shown, the BS 900 may include a processor 902, amemory 904, an IAB communication module 908, a transceiver 910 includinga modem subsystem 912 and a RF unit 914, and one or more antennas 916.These elements may be in direct or indirect communication with eachother, for example via one or more buses.

The processor 902 may have various features as a specific-typeprocessor. For example, these may include a CPU, a DSP, an ASIC, acontroller, a FPGA device, another hardware device, a firmware device,or any combination thereof configured to perform the operationsdescribed herein. The processor 902 may also be implemented as acombination of computing devices, e.g., a combination of a DSP and amicroprocessor, a plurality of microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration.

The memory 904 may include a cache memory (e.g., a cache memory of theprocessor 902), RAM, MRAM, ROM, PROM, EPROM, EEPROM, flash memory, asolid state memory device, one or more hard disk drives, memristor-basedarrays, other forms of volatile and non-volatile memory, or acombination of different types of memory. In some embodiments, thememory 904 may include a non-transitory computer-readable medium. Thememory 904 may store instructions 906. The instructions 906 may includeinstructions that, when executed by the processor 902, cause theprocessor 902 to perform operations described herein. Instructions 906may also be referred to as code, which may be interpreted broadly toinclude any type of computer-readable statement(s) as discussed abovewith respect to FIG. 7.

The IAB communication module 908 may be implemented via hardware,software, or combinations thereof. For example, the IAB communicationmodule 908 may be implemented as a processor, circuit, and/orinstructions 906 stored in the memory 904 and executed by the processor902. The IAB communication module 908 may be used for various aspects ofthe present disclosure. For example, the IAB communication module 908 isconfigured to maintain multiple synchronization references, providesynchronization information (e.g., including timing and/or frequency)associated with the synchronization references to other nodes (e.g., theBSs 105 and the UEs 115 and 800), receive synchronization informationfrom other nodes, receive synchronization adjustment commands, adjustsynchronization references based on the received synchronizationinformation or the received commands, receive scheduling information(e.g., gap periods, transmission timing, and/or reception timing) forcommunication with nodes at a higher level (e.g., less hops away from ananchor 115 c than the BS 115), determine scheduling information forcommunication with nodes at a lower level (e.g., more hops away from ananchor 115 c than the BS 115), and/or communicate with nodes based onthe received scheduling information and the determined schedulinginformation, as described in greater detail herein.

As shown, the transceiver 910 may include the modem subsystem 912 andthe RF unit 914. The transceiver 910 can be configured to communicatebi-directionally with other devices, such as the UEs 115 and/or anothercore network element. The modem subsystem 912 may be configured tomodulate and/or encode data according to a MCS, e.g., a LDPC codingmethod, a turbo coding method, a convolutional coding method, a digitalbeamforming method, etc. The RF unit 514 may be configured to process(e.g., perform analog to digital conversion or digital to analogconversion, etc.) modulated/encoded data from the modem subsystem 912(on outbound transmissions) or of transmissions originating from anothersource such as a UE 115. The RF unit 914 may be further configured toperform analog beamforming in conjunction with the digital beamforming.Although shown as integrated together in transceiver 910, the modemsubsystem 912 and the RF unit 914 may be separate devices that arecoupled together at the BS 105 to enable the BS 105 to communicate withother devices.

The RF unit 914 may provide the modulated and/or processed data, e.g.data packets (or, more generally, data messages that may contain one ormore data packets and other information), to the antennas 916 fortransmission to one or more other devices. This may include, forexample, transmission of information to complete attachment to a networkand communication with a camped UE 115 according to embodiments of thepresent disclosure. The antennas 916 may further receive data messagestransmitted from other devices and provide the received data messagesfor processing and/or demodulation at the transceiver 910. The antennas916 may include multiple antennas of similar or different designs inorder to sustain multiple transmission links.

FIG. 10 is a flow diagram of a method 1000 for communicating in an IABnetwork according to embodiments of the present disclosure. The networkmay be similar to the networks 100 and 200; and may be configured withthe topology 300. Steps of the method 1000 can be executed by acomputing device (e.g., a processor, processing circuit, and/or othersuitable component) of a wireless communication device, such as the BSs105 and 800 and the UEs 115 and 900. The method 1000 may employ similarmechanisms as described with respect to FIGS. 3 to 9. As illustrated,the method 1000 includes a number of enumerated steps, but embodimentsof the method 1000 may include additional steps before, after, and inbetween the enumerated steps. In some embodiments, one or more of theenumerated steps may be omitted or performed in a different order.

At step 1010, the method 1000 includes transmitting, by the firstwireless communication device, a first transmission to the secondwireless device during a first one of the plurality of slots.

At step 1020, the method 1000 includes receiving, by the first wirelesscommunication device, a second transmission from the second wirelessdevice during a second one of the plurality of slots, the secondtransmission including link quality information about the firsttransmission and scheduling a third transmission between the first andsecond wireless devices.

In a first aspect, the first wireless communication device transmits afirst transmission to a second wireless device during a first one of aplurality of slots; and receives a second transmission from the secondwireless device during a second one of the plurality of slots, thesecond transmission including link quality information about the firsttransmission and scheduling a third transmission between the first andsecond wireless devices. In an aspect, the first and second wirelessdevices do not have a parent child relationship.

In a second aspect, in combination with the first aspect, the firstwireless communication device may receive the third transmission fromthe second wireless communication device. In a third aspect, incombination with the first aspect, the first wireless communicationdevice may transmit the third transmission from the second wirelesscommunication device.

In a fourth aspect, in combination with any of the first to thirdaspects, the link quality information about the first transmissionincludes a least one or more combinations of CQI, reference signalreceived power (RSRP), signal to noise ratio (SNR), reference signalreceived quality (RSRQ), RSSI, beam index, beam coherence time, and beamquality.

In a fifth aspect, in combination with any of the first to fourthaspects, the second transmission includes one or more of an ACK/NACK fordata transmitted during the first transmission, and a scheduling request(SR) for a subsequent communication between the first and secondwireless communication devices.

In a sixth aspect, in combination with any of the first to fifthaspects, each of the plurality of slots includes a control channel and adata channel, and the first wireless device is configured to receive oneor more of the link quality information, the ACK/NACK, and the SR in oneof the control channel or the data channel of the second slot.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general-purpose processor may be a microprocessor,but in the alternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described above can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations. Also, as used herein, including in the claims, “or” as usedin a list of items (for example, a list of items prefaced by a phrasesuch as “at least one of” or “one or more of”) indicates an inclusivelist such that, for example, a list of [at least one of A, B, or C]means A or B or C or AB or AC or BC or ABC (i.e., A and B and C).

As those of some skill in this art will by now appreciate and dependingon the particular application at hand, many modifications, substitutionsand variations can be made in and to the materials, apparatus,configurations and methods of use of the devices of the presentdisclosure without departing from the spirit and scope thereof. In lightof this, the scope of the present disclosure should not be limited tothat of the particular embodiments illustrated and described herein, asthey are merely by way of some examples thereof, but rather, should befully commensurate with that of the claims appended hereafter and theirfunctional equivalents.

What is claimed is:
 1. A method of wireless communication by a firstwireless communication device with a second wireless communicationdevice that does not have a parent-child relationship with the firstwireless communication device because the first wireless communicationdevice is not in a path of communication between the second wirelesscommunication device and a core network, the method comprising:transmitting, by the first wireless communication device, a firsttransmission to the second wireless communication device during a firstone of a plurality of slots; receiving, by the first wirelesscommunication device, a second transmission from the second wirelesscommunication device during a second one of the plurality of slots, thesecond transmission including link quality information about the firsttransmission and scheduling a third transmission between the firstwireless communication device and the second wireless communicationdevice, wherein the link quality information about the firsttransmission includes at least one or more combinations of beam index,or beam coherence time; receiving data, using the first wirelesscommunication device, from the second wireless communication device viaa sidelink formatted slot; and transmitting, using the first wirelesscommunication device, to the second wireless communication device viathe sidelink formatted slot, a physical downlink control channel (PDCCH)comprising an ACK/NACK associated with the data received from the secondwireless communication device or a physical downlink shared channel(PDSCH) comprising the ACK/NACK associated with the data received fromthe second wireless communication device.
 2. The method of claim 1,further comprising receiving by the first wireless communication devicethe third transmission from the second wireless communication device. 3.The method of claim 1, further comprising transmitting by the firstwireless communication device the third transmission to the secondwireless communication device.
 4. The method of claim 1, wherein thesecond transmission includes one or more of an ACK/NACK for datatransmitted during the first transmission, or a scheduling request (SR)for a subsequent communication between the first and second wirelesscommunication devices.
 5. The method of claim 4, wherein each of theplurality of slots includes a control channel and a data channel, andthe first wireless communication device is configured to receive one ormore of the link quality information, the ACK/NACK, or the SR in one ofthe control channel or the data channel of the second slot.
 6. Awireless communication apparatus comprising: a transceiver; a processor;and a memory containing instruction for causing the processor totransmit a first transmission to another wireless device during a firstone of a plurality of slots, wherein the apparatus does not have aparent-child relationship with the other wireless communication devicebecause the apparatus is not in a path of communication between theother wireless communication device and a core network; receive a secondtransmission from the other wireless device during a second one of theplurality of slots, the second transmission including link qualityinformation about the first transmission and scheduling a thirdtransmission between the apparatus and the other wireless communicationdevice, wherein the link quality information about the firsttransmission includes at least one or more combinations of beam index,or beam coherence time; receive data from the other wirelesscommunication device via a sidelink formatted slot; and transmit, to theother wireless communication device via the sidelink formatted slot, aphysical downlink control channel (PDCCH) comprising an ACK/NACKassociated with the data received from the other wireless communicationdevice or a physical downlink shared channel (PDSCH) comprising theACK/NACK associated with the data received from the other wirelesscommunication device.
 7. The apparatus of claim 6, wherein the memoryfurther includes instructions for causing the processor to receive thethird transmission from the other wireless communication device.
 8. Theapparatus of claim 6, wherein the memory further includes instructionsfor receiving, in the second transmission, one or more of an ACK/NACKfor data transmitted during the first transmission, or a schedulingrequest (SR) for a subsequent communication.
 9. The apparatus of claim8, wherein each of the plurality of slots includes a control channel anda data channel, and the memory further includes instructions for causingthe processor to receive one or more of the link quality information,the ACK/NACK, and the SR in one of the control channel or the datachannel of the second slot.
 10. A wireless communication devicecomprising: means for transmitting a first transmission to anotherwireless communication device during a first one of a plurality ofslots, the wireless communication device having a parent-child relationwith the other wireless communication device because the wirelesscommunication device is not in a path of communication between the otherwireless communication device and a core network; means for receivingfrom the other wireless communication device a second transmissionduring a second one of the plurality of slots, the second transmissionincluding link quality information about the first transmission andscheduling a third transmission between the wireless communicationdevice and the other wireless communication device, wherein the linkquality information about the first transmission includes at least oneor more combinations of beam index, or beam coherence time; means forreceiving data, from the other wireless communication device via asidelink formatted slot; and means for transmitting, to the otherwireless communication device via the sidelink formatted slot, aphysical downlink control channel (PDCCH) comprising an ACK/NACKassociated with the data received from the other wireless communicationdevice or a physical downlink shared channel (PDSCH) comprising theACK/NACK associated with the data received from the other wirelesscommunication device.
 11. The wireless communication device of claim 10,wherein the means for transmitting further comprising means fortransmitting the third transmission.
 12. The wireless communicationdevice of claim 10, wherein the means for receiving further comprisingmeans for receiving the third transmission.
 13. The wirelesscommunication device of claim 10, wherein the means for receivingfurther comprises means for receiving one or more of an ACK/NACK fordata transmitted during the first transmission, or a scheduling request(SR) for a subsequent communication between the wireless communicationdevice and the other wireless communication device.
 14. The wirelesscommunication device of claim 13, wherein each of the plurality of slotsincludes a control channel and a data channel, and the means forreceiving further comprises means for receiving one or more of the linkquality information, the ACK/NACK, and the SR in one of the controlchannel or the data channel of the second slot.
 15. A non-transitorycomputer readable medium including program instructions stored thereonfor: transmitting, by a first wireless communication device, a firsttransmission to a second wireless communication device during a firstone of a plurality of slots wherein the second wireless communicationdevice does not have a parent-child relationship with the first wirelesscommunication device because the first wireless communication device isnot in a path of communication between the second wireless communicationdevice and a core network; and receiving, by the first wirelesscommunication device, a second transmission from the second wirelesscommunication device during a second one of the plurality of slots, thesecond transmission including link quality information about the firsttransmission and scheduling a third transmission between the first andsecond wireless communication devices, wherein the link qualityinformation about the first transmission includes at least one or morecombinations of beam index, or beam coherence time; receiving data,using the first wireless communication device, from the second wirelesscommunication device via a sidelink formatted slot; and transmitting,using the first wireless communication device, to the second wirelesscommunication device via the sidelink formatted slot, a physicaldownlink control channel (PDCCH) comprising an ACK/NACK associated withthe data received from the second wireless communication device or aphysical downlink shared channel (PDSCH) comprising the ACK/NACKassociated with the data received from the second wireless communicationdevice.
 16. The non-transitory computer readable medium of claim 15,further comprising program instructions for receiving by the firstwireless communication device the third transmission from the secondwireless communication device.
 17. The non-transitory computer readablemedium of claim 15, further comprising program instructions fortransmitting by the first wireless communication device the thirdtransmission to the second wireless communication device.
 18. Thenon-transitory computer readable medium of claim 15, further comprisingprogram instructions for receiving, in the second transmission, one ormore of an ACK/NACK for data transmitted during the first transmission,or a scheduling request (SR) for a subsequent communication between thefirst and second wireless communication devices.
 19. The non-transitorycomputer readable medium of claim 18, wherein each of the plurality ofslots includes a control channel and a data channel, the non-transitorycomputer readable medium further comprising program instructions forreceiving one or more of the link quality information, the ACK/NACK, orthe SR in one of the control channel or the data channel of the secondslot.